It is known that there are labeling machines designed to process labels printed on a continuous film that is unwound from a motorized reel, and that said film can be pre-pasted, i.e., provided with paste, at one face, or not, and in this case suitable pasting means are provided within the machine.
Such labeling machines comprise a drum that accompanies the film, retaining it so that it adheres to the surface by way of suction generated at the surface, cutting the individual labels up to being applied to corresponding containers conveyed by conveyance means, which are commonly constituted by a rotating carousel.
The film of the labels is fed to the drum by means of a feed roller, which, in order to be able to work correctly at the high speeds currently required, needs to receive the film unwound from the reel in extremely low and constant tension conditions, the film being further aligned at a constant height.
For this purpose, the background art provides for the presence of tensioning devices combined with alignment devices, which however are not entirely satisfactory.